code: def testPolicy(self):
      agent = ddpg_agent.DdpgAgent(
          self._time_step_spec,
          self._action_spec,
          actor_network=self._unbounded_actor_net,
          critic_network=self._critic_net,
          actor_optimizer=None,
          critic_optimizer=None,
      )
  
      observations = [tf.constant([[1, 2]], dtype=tf.float32)]
      time_steps = ts.restart(observations)
      action_step = agent.policy.action(time_steps)
      self.assertEqual(action_step.action[0].shape.as_list(), [1, 1])
  
      self.evaluate(tf.compat.v1.global_variables_initializer())
      actions_ = self.evaluate(action_step.action)
      self.assertTrue(all(actions_[0] <= self._action_spec[0].maximum))
      self.assertTrue(all(actions_[0] >= self._action_spec[0].minimum))
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tensorflow
  from tf_agents.agents.ddpg import ddpg_agent
  from tf_agents.networks import network
  from tf_agents.specs import tensor_spec
  from tf_agents.trajectories import policy_step
  from tf_agents.trajectories import time_step
  from tf_agents.trajectories import trajectory
  from tf_agents.utils import common
  from tf_agents.utils import test_utils
label_desc: Use image node_id 5 for calling the DdpgAgentTest obj's underlying member method code with example usage: obj.testPolicy() without return types